Engine runs rough and stalls after tune up on 1993 Toyota Previa

Engine was running fine, but due for routine tune-up. Replaced ignition coil, distributor cap and rotor, spark plugs and spark plug wires. Now engine will intermittently run smooth and then rough, and often stall, with no particular pattern. When restarting, it may turn over fast then slow. Re-installed old parts, and same thing occurs.

When you changed out the ignition coil, distributor cap and the spark plug wires, are you sure they're in the right place? Also, the distributor cap can rotate to adjust the ignition timing, which will cause the car to run very poorly like you have described. Hope this helps!